Agricultural ditches (e.g., irrigation ditches) roadway ditches, etc. often must be burned to remove undesired weeds, grass or other growth. Conventional devices which have been used for these purposes include hand-carried propane burners or larger burners which are mounted on trailers and towed behind a tractor. Normally an operator must be positioned on the trailer to control and direct an elongated boom having a burner nozzle on its outer end. Another person operates the tractor to tow the trailer along the area to be burned. Thus, two persons are required to operate the apparatus. The operation is also time-consuming. Another disadvantage of that particular type of apparatus is that the person on the trailer gets bounced around as the equipment moves over rough ground. Also, the trailer operator is exposed to the heat, smoke and close flame at an unsafe distance. A further disadvantage of trailer units is that they have tires which can go flat.
Another type of commercial burning apparatus requires propane fuel. Such apparatus does not include an ignition source. Rather, the operator must start a fire under the burner head to light it, thereby creating an inconvenience and possibly a dangerous situation.
Another type of commercial burning apparatus (sold by Harsh) involves the use of diesel fuel for the burner, but it also requires the use of gasoline to power a 110 volt AC generator. The operator must inconveniently start and stop the generator from outside the tractor cab. The diesel burner head designs are not very efficient. Another disadvantage is that the fuel to air mixture is fixed. Also, the ignition system is complex and does not work well.
U.S. Pat. No. 4,722,324 (Amen) describes weed burning apparatus which can be mounted on a conventional three-point hitch on a tractor. The burning apparatus utilizes a single elongated straight boom which can be twenty or more feet long. The boom is pivotally mounted intermediate its ends on an upright support post, and a hydraulic cylinder is used to pivot the boom up and down. It can also be turned from side to side. Because the boom is straight, and because it is a single length of tubing, it is not capable of bending or folding in the middle. Consequently, the flame at the outer end of the boom is always separated from the tractor by a distance equal to the length of the straight boom. Further, because the boom is straight, it cannot reach upwardly and then down over a ditch bank into a ditch to be burned.
A further disadvantage of previous weed burners is that the very long boom extends twenty feet or more behind the tractor during transport. This situation thus presents a safety hazard during transport of the apparatus. If the boom is turned to one side it creates a different type of safety hazard because it can become caught on utility poles or posts.
U.S. Pat. No. 2,839,047 (Davisson) describes weed burning apparatus in which a boom can be turned from side to side with a sprocket and chain mechanism which allows for unacceptable movement of the boom at its outer end. The patent does not describe a boom which can be folded in the middle.
U.S. Pat. No. 3,727,346 (Kramer) describes a flame cultivator for row crops. The apparatus does not include a boom which can be folded in the middle.
There has not heretofore been described a weed burning apparatus which includes all of the features and advantages provided by the present invention.